Fifty years ago, two young men graduated from the same pre-university course at Victoria School.
As biology students, Francis Lee and Chou Loke Ming had gone on field trips to the Southern Islands, peering through the clear waters and marvelling at corals shaped like rotund mushrooms or branching like antlers.
Their paths branched too. One went to Britain where he qualified as a "no-good lawyer". The other stayed in Singapore and became a distinguished marine biologist.
Then, the lives of Mr Lee, the lawyer, and Professor Chou, the biologist, converged again on a common cause: marine conservation. Now, the past three decades of their work have contributed to the establishment of Singapore's first marine park, announced earlier this month - a 40ha patch that includes the Sisters' Islands and reefs off nearby St John's Island and Pulau Tekukor.
When Mr Lee was growing up in Siglap, the sea was ever-present. Kelongs dotted the coastline, which had yet to be reclaimed, and fishermen sold the day's catch along Joo Chiat Road. "Jalan Ulu Siglap was named because beyond that it was all jungle," quips Mr Lee, now 68.
When he came back from his studies in London, he found his old neighbourhood transformed. "I was amazed at the speed with which we were executing our land reclamation. It was right on my doorstep," he says.
The young corporate lawyer took up scuba-diving and found the Southern Islands also affected by reclamation. In the 1960s and 1970s, the marine environment here was in dire straits. Massive land reclamation projects silted the once- clear waters around the southern reefs. Sisters' Islands, along with other southern islands earmarked for recreation, were partly reshaped to create artificial lagoons.
Soil from excavations was indiscriminately dumped in the sea, and boats dropped anchor on corals. In all, about 60 per cent of reef cover was lost to development.
Meanwhile, Prof Chou took up scuba-diving, too, to switch his field of study from house lizards to the marine realm. Even in the silty waters, he and his colleagues mapped reefs and saw vast globe- like corals, crinkly ones resembling cabbage leaves, fronds of green and brown algae, and delicate starfish.
Already, a small group of marine conservation advocates was struggling to be heard. At the time, National University of Singapore Professor Leo Tan was a lecturer at the University of Singapore.